Method and apparatus for an adjustable damper

ABSTRACT

A vehicle suspension damper including: a cylinder; a piston assembly; and an adjuster, wherein the piston assembly compresses fluid as it moves within the cylinder and the adjuster obstructs fluid flow from a first side of a damping piston of the piston assembly to a second side of the damping piston.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and is a continuation of theco-pending patent application, Ser. No. 16/416,045, filed on May 17,2019, entitled “METHOD AND APPARATUS FOR AN ADJUSTABLE DAMPER” by Cox etal., assigned to the assignee of the present application, havingAttorney Docket No. FOX-P5-10-12US.CON, and is hereby incorporated byreference in its entirety herein.

The 16/416,045 application claims priority to and is a continuation ofthe patent application, Ser. No. 13/891,469, filed on May 10, 2013, NowU.S. Pat. No. 10,330,171, entitled “METHOD AND APPARATUS FOR ANADJUSTABLE DAMPER” by Cox et al., assigned to the assignee of thepresent application, having Attorney Docket No. FOX-P5-10-12US, and ishereby incorporated by reference in its entirety herein.

The 13/891,469 application claims the benefit of and claims priority ofU.S. provisional patent application Ser. No. 61/645,465, filed on May10, 2012, entitled “METHOD AND APPARATUS FOR AN ADJUSTABLE DAMPER” byCox et al., assigned to the assignee of the present application, havingAttorney Docket No. FOX-P5-10-12.PRO, and is hereby incorporated byreference in its entirety herein.

This patent application is related to, and contemplates integrationwith, the subject matter of: U.S. provisional patent application serialnumber 61/361,127, filed on Jul. 2, 2010, by John Marking, havingAttorney Docket No. FOXF/0047USL, which is incorporated herein byreference; U.S. provisional patent application Ser. No. 61/491,858,filed on May 31, 2011, by Everet Ericksen, having Attorney Docket No.FOXF/0055USL which is incorporated herein by reference; U.S. provisionalpatent application Ser. No. 61/296,826, filed on Jan. 20, 2010, by JohnMarking, having Attorney Docket No. FOXF/0043USL which is incorporatedherein by reference; U.S. provisional patent application Ser. No.61/143,152, filed Jan.7, 2009, by John Marking, having Attorney DocketNo. FOXF/0032L which is herein incorporated by reference; U.S. patentapplication Ser. No. 12/684,072 (the “'072 Application”), filed on Jan.7, 2010, now abandoned, by John Marking, having Attorney Docket No.FOXF/0032US, which is herein incorporated by reference; and U.S. patentapplication Ser. No. 13/485,401, filed on May 31, 2012, now abandoned,by Ericksen et al., having Attorney Docket No. FOXF/0055US, which isherein incorporated by reference.

BACKGROUND Field of the Invention

Embodiments generally relate to a damper assembly for a vehicle. Morespecifically, the invention relates to a “fluid bypass” for use with avehicle suspension.

Description of the Related Art

Vehicle suspension systems typically include a spring component orcomponents and a dampening component or components. Typically,mechanical springs, like helical springs are used with some type ofviscous fluid-based dampening mechanism and the two are mountedfunctionally in parallel. In some instances, a spring may comprisepressurized gas and features of the damper or spring areuser-adjustable, such as by adjusting the air pressure in a gas spring.A damper may be constructed by placing a damping piston in afluid-filled cylinder (e.g., liquid such as oil). As the damping pistonis moved in the cylinder, fluid is compressed and passes from one sideof the piston to the other side. Often, the piston includes ventsthere-through which may be covered by shim stacks to provide fordifferent operational characteristics in compression or extension.

Conventional damping components provide a constant damping rate duringcompression or extension through the entire length of the stroke. As thesuspension component nears full compression or full extension, thedamping piston can “bottom out” against the end of the damping cylinder.Allowing the damping components to “bottom out” may cause the componentsto deform or break inside the damping cylinder.

As the foregoing illustrates, what is needed in the art are improvedtechniques for varying the damping rate including to lessen the risk ofthe suspension “bottoming out”.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A depicts an asymmetric bicycle fork having a damping leg and aspring leg, according to an embodiment.

FIG. 1B depicts a shock absorber assembly including an internal bypassdamper, in accordance with an embodiment.

FIG. 2 depicts a cross-sectional side elevation view of a shock absorberassembly, in accordance with an embodiment.

FIG. 3 depicts a cross-sectional view of an eyelet assembly as attachedat an end of a shaft, in accordance with an embodiment.

FIG. 4 depicts a cross-sectional side elevation view of a shock absorberassembly, in accordance with an embodiment.

FIG. 5 depicts a perspective view of an eyelet assembly exposing aconnection between a damping adjustment lever and a rod, as well asrotational travel limits for the damping adjustment lever that includesthe walls of the lever slot, in accordance with an embodiment.

FIG. 6 depicts a perspective view of the eyelet assembly showing thedamping adjustment lever within the lever slot, in accordance with anembodiment.

FIG. 7 depicts a perspective view of the damping piston, in accordancewith an embodiment.

FIG. 8 depicts a perspective view of the damping piston of FIG. 7 asrelated to the eyelet assembly of FIG. 3, in accordance with anembodiment.

FIG. 9 depicts a cross-sectional top side elevation view of a shockabsorber assembly, in accordance with an embodiment.

FIG. 10 depicts a perspective view of a shock absorber assembly, with aportion of the shock absorber assembly shown in a cross-sectional sideelevation view, illustrating the related mechanisms therein, inaccordance with an embodiment.

FIG. 11 depicts a perspective view of a lower eyelet assembly, with aportion of the lower eyelet assembly shown in a cross-sectional sideelevation view, in accordance with an embodiment.

FIG. 12 depicts the windows, such as windows 128 (of FIGS. 4) and 300(of FIGS. 13A-13K and FIGS. 17A-17E), being opened or closed by therespective excursion or incursion of a needle during rebound orcompression of the shock absorber assembly, in accordance with anembodiment.

FIGS. 13A-13E depict a cross-sectional side elevation views of a needletype monotube damper in various stages of movement sequentially from anextended length to a compressed position, in accordance withembodiments.

FIG. 13F depicts an enlarged cross-section side elevation view of aportion of the needle type monotube damper of FIG. 13D, in accordancewith an embodiment.

FIGS. 13G-13I depict cross-sectional side elevation views of a needletype monotube damper in various stages of movement sequentially from anextended length to a compressed position, in accordance with anembodiment.

FIGS. 13J and 13K depict perspective views of the castellated (orslotted check valve), in accordance with an embodiment.

FIG. 14A depicts a perspective view of aspects of embodiments, in acompressed position, in accordance with embodiments.

FIG. 14B depicts a cross-sectional side elevation view of FIG. 14A,aspects of embodiments having a “piggy back” reservoir (versus amonotube), in a compressed position, in accordance with embodiments.

FIG. 15A depicts a perspective view of aspects of embodiments, in anextended position, in accordance with embodiments.

FIG. 15B depicts a cross-sectional side elevation view of FIG. 15A,aspects of embodiments having a “piggy back” reservoir (versus amonotube), in an extended position, in accordance with embodiments.

FIG. 16A depicts an enlarged cross-sectional top elevation view of thetop 1410 of the piston assembly depicted in FIG. 14B, in accordance withan embodiment.

FIG. 16B depicts an enlarged cross-sectional top elevation view of thebottom 1415 of the piston assembly that is depicted in 14B, inaccordance with an embodiment.

FIG. 16C depicts an enlarged perspective side view of the pistonassembly, in accordance with an embodiment.

FIG. 16D depicts a cross-sectional side elevation view of FIG. 16A atthe Section B-B, in accordance with an embodiment.

FIG. 16E depicts a cross-sectional side elevation view of FIG. 16B atthe Section C-C, in accordance with an embodiment.

FIG. 16F depicts an enlarged side perspective* view of the detail 1605,showing the piston 310, in accordance with an embodiment.

FIG. 17A depicts a perspective view of a shaft 205, in accordance withan embodiment.

FIG. 17B depicts a cross-sectional view of the shaft 205 of FIG. 17A, inaccordance with an embodiment.

FIG. 17C depicts an enlarged view of the detail 1705 of FIG. 17B, inaccordance with an embodiment.

FIG. 17D depicts an enlarged view of the detail 1525 of FIG. 17A, inaccordance with an embodiment.

FIG. 17E depicts an enlarged view of the detail 1530 of FIG. 17A, inaccordance with an embodiment.

The drawings referred to in this description should be understood as notbeing drawn to scale except if specifically noted.

SUMMARY

An embodiment of the present technology, a vehicle suspension damper,includes: a cylinder; a piston assembly; and an adjuster coupled withthe piston assembly, wherein the piston assembly compresses fluid as itmoves within the cylinder and the adjuster obstructs fluid flow from afirst side of a damping piston of the piston assembly to a second sideof the damping piston.

In one embodiment, the adjuster of the vehicle suspension damperincludes: a rotatable valve configured for rotating from a firstposition to a second position. The rotatable valve includes: at leastone passageway there through, wherein when the rotatable valve is in atleast one of the first position and the second position, the fluid flowis obstructed in its flow through the at least one passageway and fromthe first side of the damping piston to the second side of the dampingpiston. In one embodiment, the adjuster of the vehicle suspension damperincluding the rotatable valve, further includes a damping adjustmentlever coupled with the rotatable valve, the damping adjustment leverbeing movable and configured for, upon movement of the dampingadjustment lever, rotating the rotatable valve from the first positionto the second position. In one embodiment the adjuster of the vehiclesuspension damper that includes the rotatable valve and the dampingadjustment lever, further includes a control rod rotationally fixed tothe damping adjustment lever and the rotatable valve, wherein thecontrol rod rotationally responds to the movement of the dampingadjustment lever by rotating the rotatable valve in proportion to themovement.

In one embodiment, the adjuster of the vehicle suspension damper thatincludes the rotatable valve further includes a motive source coupledwith the rotatable valve, the motive source configured for providinginput, wherein in response to the input, the rotatable valve rotatesfrom the first position to the second position. In one embodiment, themotive source includes: an electric input. In another embodiment, themotive source includes: an hydraulic input.

In one embodiment the adjuster of the vehicle suspension damper thatincludes the rotatable valve and the motive source includes a controlrod coupled with the motive source and the rotatable valve, wherein thecontrol rod rotationally responds to the input of motive source byrotating the rotatable valve according to the input.

In one embodiment, the vehicle suspension damper that includes thecylinder, the piston assembly, and the adjuster, further includes atleast one vented path there through, wherein the fluid flows through theat least one vented path when the fluid moves from the first side of thedamping piston to the second side of the damping piston, and furtherincludes at least one set of shims coupled to the at least one ventedpath, wherein the at least one set of shims obstructs the at least onevented path during at least one of compression and rebound of thevehicle suspension damper.

In one embodiment, the vehicle suspension damper that includes thecylinder, the piston assembly, and the adjuster, further includes ashaft positioned within the cylinder, the shaft including at least onewindow through which the fluid flows from the first side of the dampingpiston to the second side of the damping piston, and further includes aneedle valve positioned with the cylinder, whereupon in response to anexcursion out of a bore or incursion into the bore of the needle valveduring a rebound or compression, respectively, of the vehicle suspensiondamper, the at least one window of the shaft opens or closes,respectively, thereby changing a flow of the fluid through the shaftfrom the first side of the damping piston to the second side of thedamping piston.

One embodiment of the present technology includes a method for dampingincluding: applying a compression to a damping fluid, forcing at least afirst portion of the compressed damping fluid through an adjustable flowregulator, and delivering regulated damping fluid into pressurecommunication with a gas charge. In one embodiment, the method furtherincludes, in response to positioning input, positioning the adjustableflow regulator into at least one of a first position and a secondposition such that the at least a first portion of the compresseddamping fluid is enabled to flow through the adjustable flow regulator.

In one embodiment, the forcing of the at least a first portion of thecompressed damping fluid through an adjustable flow regulator includesforcing the at least a first portion of compressed damping fluid throughat least one passageway of a rotatable valve of the adjustable flowregulator, wherein the rotatable valve is in a fully open position. Inone embodiment, the positioning includes, in response to the positioninginput, rotating a rotatable valve to the at least one of the firstposition and the second position, wherein the rotatable valve comprisesat least one passageway through which the at least a first portion ofthe compressed damping fluid is forced.

In another embodiment, the forcing of the at least a first portion ofthe compressed damping fluid through an adjustable flow regulatorincludes forcing at least a first portion of the compressed dampingfluid through at least one passageway of a rotatable valve of theadjustable flow regulator, wherein the rotatable valve is configured forrotating from a first position to a second position and the rotatablevalve is in a partially open position.

In one embodiment, the method further includes obstructing a flow of atleast a second portion of the compressed damping fluid through theadjustable flow regulator, wherein the adjustable flow regulatorcomprises a rotatable valve configured for rotating from a firstposition to a second position, the rotatable valve including at leastone passageway there through, wherein when the rotatable valve is in atleast one of the first position and the second position, the flow of theat least the second portion of the compressed damping fluid isobstructed in its flow through the at least one passageway.

In one embodiment, the method further includes forcing the at leastfirst portion of compressed damping fluid through at least one set ofshim stacks configured for at least partially obstructing a flow ofcompressed damping fluid.

In one embodiment, the method further includes forcing the at leastfirst portion of the compressed damping fluid through at least onewindow of a shaft, wherein the shaft encompasses at least a portion ofthe adjustable flow regulator.

One embodiment of the present technology includes an adjustment systemfor adjusting a flow of fluid through a vehicle suspension damper. Theadjustment system includes: a rotatable valve; a damping adjustmentlever; and a control rod. The rotatable valve is configured for rotatingfrom a first position to a second position. The rotatable valve includesat least one passageway there through, wherein upon a movement of therotatable valve effects a change in the flow of the fluid through thevehicle suspension damper. The damping adjustment lever is configuredfor, upon movement, rotating the rotatable valve from the first positionto the second position. The control rod is rotationally fixed to thedamping adjustment lever and the rotatable valve, wherein the controlrod rotationally responds to the movement of the damping adjustmentlever by rotating the rotatable valve in proportion to the movement.

In one embodiment of the adjustment system, the adjustment system iscoupled to a piston assembly positioned within a cylinder of the vehiclesuspension damper, wherein the piston assembly compresses the fluid asthe piston assembly moves within the cylinder.

In one embodiment of the adjustment system, the change that is effectedis an obstruction of the flow of the fluid from a first side of adamping piston of the piston assembly to a second side of the dampingpiston. Further, in one embodiment, the damping piston includes at leastone vented path there through and at least one set of shims. The fluidflows through the at least one vented path when the fluid moves from thefirst side of the damping piston to the second side of the dampingpiston. The at least one set of shims is coupled to the at least onevented path, wherein the at least one set of shims obstructs the atleast one vented path during at least one of compression and rebound ofthe vehicle suspension damper.

In one embodiment, the adjustment system further includes: a shaft and aneedle valve positioned within the cylinder. The shaft includes at leastone window through which the fluid flows from the first side of thedamping piston to the second side of the damping piston. In response toan excursion out of a bore of the needle valve or incursion into thebore during a rebound or compression, respectively, of the vehiclesuspension damper, the at least one window of the shaft opens or closes,respectively, thereby changing a flow of the fluid through the shaftfrom the first side of the damping piston to the second side of thedamping piston.

In one embodiment, the adjustment system further includes: a motivesource coupled with the control rod. The motive source is configured forproviding input, wherein in response to the input, the control rodrotationally responds to the input from the motive source by rotatingthe rotatable valve according to the input. In various embodiments, theinput is electric and/or hydraulic.

BRIEF DESCRIPTION

Reference will now be made in detail to embodiments of the presenttechnology, examples of which are illustrated in the accompanyingdrawings. While the technology will be described in conjunction withvarious embodiment(s), it will be understood that they are not intendedto limit the present technology to these embodiments. On the contrary,the present technology is applicable to alternative embodiments,modifications and equivalents, which may be included within the spiritand scope of the invention as defined by the appended claims.

Furthermore, in the following description of embodiments, numerousspecific details are set forth in order to provide a thoroughunderstanding of the present technology. However, the present technologymay be practiced without these specific details. In other instances,well known methods, procedures, and components have not been describedin detail as not to unnecessarily obscure aspects of the presentdisclosure.

Embodiments describe an adjustable vehicle suspension damper enabled tovary the damping rate. The adjustable vehicle suspension damper includesa piston of a piston assembly and an adjuster. The piston assemblycompresses fluid moving through the vehicle suspension damper. Theadjuster obstructs fluid flow moving from a first side of the piston toa second side of the piston.

The following discussion will first briefly describe variousembodiments. The discussion then turns to a description of the FIGS.1-17E and embodiments shown therein.

Integrated damper/spring vehicle shock absorbers often include a damperbody surrounded by or used in conjunction with a mechanical spring orconstructed in conjunction with an air spring or both. The damper oftenconsists of a piston and shaft telescopically mounted in a fluid filledcylinder. The damping fluid (i.e., damping liquid) or damping liquid maybe, for example, hydraulic oil. A mechanical spring may be a helicallywound spring that surrounds or is mounted in parallel with the damperbody. Vehicle suspension systems typically include one or more dampersas well as one or more springs mounted to one or more vehicle axles. Asused herein, the terms “down”, “up”, “downward”, “upward”, “lower”,“upper”, and other directional references are relative and are used forreference only.

FIG. 1A shows an asymmetric bicycle fork 100 having a damping leg and aspring leg, according to one example embodiment. The damping legincludes an upper tube 103 mounted in telescopic engagement with a lowerleg tube 110 and having fluid damping components therein. The spring legincludes an upper tube 106 mounted in telescopic engagement with a lowerleg tube 111 and having spring components therein. The upper tubes 103,106 may be held centralized within the lower legs tubes 110, 111 by anannular bushing 108. The fork 100 may be included as a component of abicycle such as a mountain bicycle or an off-road vehicle such as anoff-road motorcycle. In some embodiments, the fork 100 may be an “upsidedown” or Motocross-style motorcycle fork.

In one embodiment, the damping components inside the damping leg includean internal piston 166 disposed at an upper end of a damper shaft 136and fixed relative thereto. The internal piston 166 is mounted intelescopic engagement with a cartridge tube 162 connected to a top cap180 fixed at one end of the upper tube 103. The interior volume of thedamping leg may be filled with a damping liquid such as hydraulic oil.The piston 166 may include shim stacks (i.e., valve members) that allowa damping liquid to flow through vented paths in the piston 166 when theupper tube 103 is moved relative to the lower leg tube 110. Acompression chamber is formed on one side of the piston 166 and arebound chamber is formed on the other side of the piston 166. Thepressure built up in either the compression chamber or the reboundchamber during a compression stroke or a rebound stroke provides adamping force that opposes the motion of the fork 100.

The spring components inside the spring leg include a helically woundspring 115 contained within the upper tube 106 and axially restrainedbetween top cap 181 and a flange 165. The flange 165 is disposed at anupper end of the riser tube 163 and fixed thereto. The lower end of theriser tube 163 is connected to the lower leg tube 111 in the spring legand fixed relative thereto. A valve plate 155 is positioned within theupper leg tube 106 and axially fixed thereto such that the valve plate155 moves with the upper tube 106. The valve plate 155 is annular inconfiguration, surrounds an exterior surface of the riser tube 163, andis axially moveable in relation thereto. The valve plate 155 is sealedagainst an interior surface of the upper tube 106 and an exteriorsurface of the riser tube 163. A substantially incompressible lubricant(e.g., oil) may be contained within a portion of the lower leg tube 111filling a portion of the volume within the lower leg tube 111 below thevalve plate 155. The remainder of the volume in the lower leg tube 111may be filled with gas at atmospheric pressure.

During compression of fork 100, the gas in the interior volume of thelower leg tube 111 is compressed between the valve plate 155 and theupper surface of the lubricant as the upper tube 106 telescopicallyextends into the lower leg tube 111. The helically wound spring 115 iscompressed between the top cap 181 and the flange 165, fixed relative tothe lower leg tube 111. The volume of the gas in the lower leg tube 111decreases in a nonlinear fashion as the valve plate 155, fixed relativeto the upper tube 106, moves into the lower leg tube 111. As the volumeof the gas gets small, a rapid build-up in pressure occurs that opposesfurther travel of the fork 100. The high pressure gas greatly augmentsthe spring force of spring 115 proximate to the “bottom-out” positionwhere the fork 100 is fully compressed. The level of the incompressiblelubricant may be set to a point in the lower leg tube 111 such that thedistance between the valve plate 155 and the level of the oil issubstantially equal to a maximum desired travel of the fork 100.

Referring now to FIG. 1B, a sectional view of a shock absorber assembly99 is depicted, in accordance with an embodiment. The shock absorberassembly 99 includes an internal bypass damper. The shock absorberassembly 99 includes a threaded body 120 (having an adjustable threadedspring 137 support thereon), a piston rod or shaft 104, a lower eyeletassembly including a lower spring support 140 and a damping adjustmentlever 102. Another type of internal bypass damper is shown and describedin U.S. Pat. No. 6,296,092 ('092 Patent), which is entirely incorporatedherein by reference.

FIG. 2 and FIG. 4 depict a cross-sectional view of a shock absorberassembly 99, in accordance with an embodiment. As shown, a dampingpiston 310 is connected to an end of the shaft 104. The interior of theshaft 104 includes a control rod 105 which, when rotated,correspondingly rotates valve 125 and its passageways 126. Note that inthe view of FIG. 2, the passageways 126 are aligned with an axisperpendicular to the page and in FIG. 4, the passageways 126 are alignedwith the plane of the page. Further, in FIG. 2 the passageways 126 (orapertures) are aligned with a solid portion of the wall of the valverecess 130, and as such the interior 131 of the shaft 104/valve recess130 is closed from fluid communication with annular flow distributor127. In FIG. 4, the passageways 126 are aligned with the shaft windows128 (note that the shaft 104/valve recess 130 is analogous to the shaft205 of FIG. 13F having the windows or flow ports), thereby allowingfluid flow between the interior 131 of the shaft 104 and the annularflow distributor 127.

FIG. 3 depicts a cross-sectional view of an eyelet assembly 112 asattached at an end of the shaft 104 (opposite the damping piston 310),including a damping adjustment lever 102 rotationally fixed to an end ofthe control rod 105, in accordance with an embodiment. When the dampingadjustment lever 102 is rotated about the long axis of the control rod105, the control rod 105 is correspondingly rotated, which in turnrotates valve 125 and passageways 126. Note that in lieu of or inaddition to the damping adjustment lever 102, a motor or other suitablemotive device (labeled “motor 302”) may be attached to control rod 105to provide rotation of the control rod 105 in response to input 302,such as electric, hydraulic (pneumatic) or other suitable input 304.

FIG. 5 depicts a cross-sectional view of the eyelet assembly 112 thatexposes a connection between the damping adjustment lever 102 and thecontrol rod 105, as well as rotational travel limits for the dampingadjustment lever 102, that includes the walls 135A and 1356(hereinafter, “walls 135”) of the damping adjustment lever slot 140, inaccordance with an embodiment.

FIG. 6 depicts a cross-sectional view of the eyelet assembly 112 showingthe damping adjustment lever 102 within the damping adjustment leverslot 140, in accordance with an embodiment.

FIG. 7 depicts a cross-sectional view of the damping piston 310. Asshown, the damping piston 310 is mounted to the valve recess 130 (theshaft 104 includes the valve recess 130; the valve recess 130 is at theupper portion of the shaft 104), having windows 128. Inside the valverecess 130 (and ultimately, inside the shaft 104) and coaxial therewithis shown valve 125 with passageways 126 (which serve as flow paths). Thedamping piston 310 includes typical compression and rebound ports (e.g.,compression port 145 and rebound port 150) (shims not shown), and alsobypass ports 320 in fluid communication with corresponding flow channels305 and annular flow distributor 127.

FIG. 8 depicts the damping piston 310 of FIG. 7 as related to the eyeletassembly 112 of FIG. 3 (and FIG. 6), in accordance with an embodiment.

FIG. 9 depicts a cross-sectional view of a shock absorber assembly 99,in accordance with an embodiment. FIG. 9 is an additional view showing aconfiguration, as in FIG. 4, where passageways 126 are aligned withwindows 128, and thereby allowing fluid communication from the interior131 of the shaft 104 to the annular flow distributor 127 andcorrespondingly to (referring to FIG. 7) flow channels 305 and bypassports 320.

FIG. 10 depicts a partial cross-sectional view of the shock absorberassembly 99, illustrating the related mechanisms therein, in accordancewith an embodiment.

FIG. 11 depicts the a cross-sectional view of a lower portion of theeyelet assembly 112, in which the lower portion of the eyelet assembly112 includes the damping adjustment lever 102 and its connection to thecontrol rod 105.

FIG. 12 depicts the windows, such as windows 128 (see FIG. 4) andwindows 128 (and flowports 305) (see FIG. 7), being opened or closed bythe respective excursion or incursion of a needle during rebound orcompression of the shock absorber assembly 99, respectively, inaccordance with an embodiment. Note that in addition to the controlfeature described herein via control rod 105 and valve 125, a needle mayalso be employed to provide a position sensitive feature.

In one embodiment, and referring to FIG. 3, the damping adjustment lever102 includes a handle 107 and an indexing mechanism 139 that retains thehandle 107 in intermediate positions between the walls 135 of thedamping adjustment lever slot 140, thereby providing “modal” dampingadjustment selection. For example, the damping adjustment lever 102 mayhave three “click in” positions corresponding to three desired dampingstiffness's resulting from three rotational positions of valve 125 (viacontrol rod 105 and damping adjustment lever 102). In one embodiment,the motor 302 is an encoder and is capable of rotating the valve 125 toan effectively infinite number of positions between valve 125 full openand valve 125 full closed. As such, the so equipped suspension (shock)may have a highly variable and selectable damping function that, forexample, could be selected from based on terrain, or speed, or otherrelevant driving factors.

In one embodiment, the shock absorber assembly 99 hereof includes theadjustment feature provided by valve 125, as well as the positionsensitive feature as provided by a needle valve. Such a shock absorberassembly would be stiffer with increased compression, but such stiffnesswould begin or baseline from a pre-selected base damping level. In oneembodiment, a shock absorber 99 hereof further includes an adjustablerebound shim preload 160 or other suitable rebound damping adjuster.

In one embodiment, the shock absorber assembly 99 herein may be used onthe front, rear, or both, of a four wheeled vehicle and the “motor” isconnected to a circuit having sensors for any or all of the vehicleroll, pitch, and yaw. The circuit further includes a programmableprocessor for receiving sensor data and signaling the appropriate motoror motors (e.g., one each at each of the four vehicle “corners”) toeither open or close the piston valve (e.g., valve 125) tocorrespondingly soften or stiffen the respective damping of the shockabsorber assembly 99. One embodiment includes sensors for braking,accelerating, and/or turning. In one embodiment, the motors arecontrolled by a switch in the cockpit of the so equipped vehicle. In oneembodiment, the switch or switches operate a circuit which suppliespower to the motor or motors. In one embodiment, the switch is wirelessand sends a signal to a circuit which supplies power to the “motor”. Inone embodiment, the switch is a personal computing device such as oneincluding a cell phone (e.g., Apple iPhone™ or Android™ device). Othersuitable motor control mechanisms may be employed.

The discussion now turns to FIGS. 13A-13K, FIGS. 14A-14B, FIGS. 15A-15B,FIGS. 16A-16F, and FIGS. 17A-17E, which are excerpted from the U.S.Provisional Patent Application Ser. No. 61/491,858 (hereinafter,“'858”). Of note, any suitable combinations of features disclosed hereinare contemplated, including combinations of the material from '858 andthat disclosed herein.

Of additional note, U.S. patent application Ser. No. 7,628,259, whichPatent is entirely incorporated herein by reference, describes someforms of compression cavitations that may occur in a damper. Needle typevariable dampers are shown in U.S. patent application Ser. Nos.5,810,128; and 6,446,771, each of which is entirely incorporated hereinby reference. An internal bypass damper is shown and described in U.S.patent application Ser. No. 6,296,092 (hereinafter, “'092 Patent”) whichis entirely incorporated herein by reference. For enhanced illustration,parts as numbered herein may be (but not necessarily) analogous withnumbered parts of the '092 Patent.

FIGS. 13A-13K depict a needle type monotube damper 1300 in variousstages of movement sequentially from an extended length to a compressedposition. Referring now to FIG. 13A, the needle type monotube damper1300 includes an internal floating piston 1305 mounted substantiallyco-axially around the needle 200 and axial movable relative thereto.Also shown is a reference to the damping liquid 1310 and the gas charge1315. FIG. 13A depicts the needle type monotube damper 1300 at itsextended length. FIG. 13B depicts the needle type monotube damper 1300in a more compressed state than that of the needle type monotube damper1300 of FIG. 13A (also referred to as the curb height). FIG. 13C depictsthe needle type monotube damper 1300 in a more compressed state thanthat of the needle type monotube damper 1300 of FIG. 13B (also referredto as the roll zone). FIG. 13D depicts the needle type monotube damper1300 in a more compressed state than that of the needle type monotubedamper 1300 of FIG. 13C. As shown, the needle 200 enters a bore of shaft205 beginning just before the “bottom-out zone”. (“Bottom out” is apoint of maximum practical leg compression.)

FIG. 13F depicts the detail 1320 of FIG. 13D, showing the needle 200 andthe shaft 205 at approximately the bottom-out zone position, inaccordance with an embodiment. As shown in FIG. 13F, the needle 200 issurrounded by the check valve 220 contained with the nut 210 fixed onthe end of the shaft 205. During the compression movement within the“bottom out” zone, the check valve 220 is moved, by fluid pressurewithin the bore 235 and flow of fluid out of the bore 235, upwardagainst the seat 225 of nut 210 and the bulk of escaping fluid must flowthrough the annular clearance 240 that dictates a rate at which theneedle 200 may further progress into the bore 235, thereby substantiallyincreasing the damping rate of the damping unit 201 proximate to the“bottom- out” zone. The amount of annular clearance 240 between theexterior surface of the needle 200 and the interior surface of the checkvalve 220 determines the additional damping rate within the “bottom-out”zone caused by the needle 200 entering the bore 235. In one embodiment,the needle 200 is tapered to allow easier entrance of the needle 200into the bore 235 through the check valve 220 upon rapid compression.

FIG. 13E depicts the needle type monotube damper 1300 in a morecompressed state than that of the needle type monotube damper 1300 ofFIG. 13D, such that the needle type monotube damper 1300 is in acompressed state.

During rebound (and hence, extension) within the “bottom-out” zone,fluid pressure in the bore 235 drops as the needle 200 is retracted andfluid flows into the bore 235, causing the check valve 220 to movetoward a valve retainer clip 215 that secures the check valve 220 withinthe nut 210. In one embodiment, the check valve 220 is castellated orslotted 230 on the face of the check valve 220 adjacent to the valveretainer clip 215 to prevent sealing the check valve 220 against thevalve retainer clip 215, thereby forcing all fluid to flow back into thebore 235 via the annular clearance 240. Instead, the castellation orslot 230 allows ample fluid flow into the bore 235 during the reboundstroke to avoid increasing the damping rate during rebound within the“bottom out” zone. The movement during the extension causes the checkvalve 220 to separate from the seat 225, thereby allowing ample flow offluid into the bore 235 during extension. The check valve 220 isradially retained with the nut 210 which has a valve recess havingradial clearance between the interior surface of the valve recess andthe exterior surface of the check valve 220, thereby allowing foreccentricity of the needle 200 relative to the shaft 205 withouthampering relative functioning of the parts (without causinginterference that could deform the components of the damping unit 201).

With reference now to FIG. 13G, FIG. 13H, and FIG. 13I, another exampleof a needle-type monotube damping unit in different states ofcompression is shown in cross-sectional side elevation views, inaccordance with an embodiment.

In one embodiment, the components included in damping unit 201 may beimplemented as one half of fork 100. In another embodiment, damping unit201 may be implemented as a portion of a shock absorber that includes ahelically-wound, mechanical spring mounted substantially coaxially withthe damping unit 201. In yet other embodiments, damping unit 201 may beimplemented as a component of a vehicle suspension system where a springcomponent is mounted substantially in parallel with the damping unit201.

As shown in FIG. 13G, the damping unit 201 is positioned in asubstantially fully extended position. The damping unit 201 includes acylinder 202, a shaft 205, and a piston 266 fixed on one end of theshaft 205 and mounted telescopically within the cylinder 202. The outerdiameter of piston 266 engages the inner diameter of cylinder 202. Inone embodiment, the damping liquid (e.g., hydraulic oil or other viscousdamping fluid) meters from one side to the other side of the piston 266by passing through vented paths formed in the piston 266. Piston 266 mayinclude shims (or shim stacks) to partially obstruct the vented paths ineach direction (i.e., compression or rebound). By selecting shims havingcertain desired stiffness characteristics, the damping effects can beincreased or decreased and damping rates can be different between thecompression and rebound strokes of the piston 266. The damping unit 201includes the internal floating piston 1305 (annular floating piston)mounted substantially co-axially around a needle 200 and axially movablerelative thereto. The needle 200 is fixed on one end of the cylinder 202opposite the shaft 205. A volume of gas is formed between the internalfloating piston 1305 and the end of cylinder 202. The gas is compressedto compensate for motion of shaft 205 into the cylinder 202, whichdisplaces a volume of damping liquid equal to the additional volume ofthe shaft 205 entering the cylinder 202.

During compression, the shaft 205 moves into the cylinder 202, causingthe damping liquid to flow from one side of the piston 266 to the otherside of the piston 266 within the cylinder 202. FIG. 13H shows theneedle 200 and shaft 205 at an intermediate position as the damping unit201 has just reached the “bottom-out” zone. In order to prevent thedamping components from “bottoming out”, potentially damaging saidcomponents, the damping force resisting further compression of thedamping unit 201 is substantially increased within the “bottom-out”zone. The needle 200 (i.e., a valve member) compresses fluid in a bore235, described in more detail in conjunction with FIG. 13F, therebydrastically increasing the damping force opposing further compression ofthe damping unit 201. Fluid passes out of the bore around the needlethrough a valve that is restricted significantly more than the ventedpaths through piston 266. As shown in FIG. 13I, the damping rate isincreased substantially within the “bottom-out” zone until the dampingunit 201 reaches a position where the damping unit 201 is substantiallyfully compressed.

FIGS. 13J and 13K illustrate the castellated or slotted check valve 220,according to one example embodiment. As shown in FIGS. 13J and 13K, thecheck valve 220 is a washer or bushing having an interior diameter sizedto have an annular clearance 240 between the interior surface of thecheck valve 220 and the exterior surface of the needle 200 when theneedle 200 passes through the check valve 220. Different annularclearances 240 may be achieved by adjusting the interior diameter of thecheck valve 220 in comparison to the diameter of the needle 200, whichcauses a corresponding change in the damping rate proximate to the“bottom-out” zone. A spiral face groove is machined into one side of thecheck valve 220 to create the castellation or slot 230. It will beappreciated that the geometry of the slot 230 may be different inalternative embodiments and is not limited to the spiral designillustrated in FIGS. 13J and 13K. For example, the slot 230 may bestraight (i.e., rectangular) instead of spiral, or the edges of the slot230 may not be perpendicular to the face of the check valve 220. Inother words, the geometry of the slot 230 creates empty space betweenthe surface of the valve retainer clip 215 and the surface of the checkvalve 220 such that fluid may flow between the two surfaces.

When assembled, the check valve 220 is oriented such that the side withthe slot 230 is proximate to the upper face of the valve retainer clip215, thereby preventing the surface of the check valve 220 from creatinga seal against the valve retainer clip 215. The slot 230 is configuredto allow fluid to flow from the cylinder 202 to bore 235 around theexterior surface of the check valve 220, which has a larger clearancethan the annular clearance 240 between the check valve 220 and theneedle 200. In one embodiment, two or more slots 230 may be machined inthe face of the check valve 220. In some embodiments, the check valve220 is constructed from high-strength yellow brass (i.e., a manganesebronze alloy) that has good characteristics enabling low frictionbetween the check valve 220 and the needle 200. In alternateembodiments, the check valve 220 may be constructed from other materialshaving suitable characteristics of strength or coefficients of friction.

FIGS. 14A-14B, FIGS. 15A-15B, FIGS. 16A-16F, and FIGS. 17A-17E showaspects of an embodiment having a “piggy back” reservoir (versusmonotube). The damper of FIGS. 14A-17E includes a needle 200 and a shaft205 having a bore 235 (the bore 235 being called out in FIG. 13F).During compression, the needle 200 enters the shaft 205 at some point(as previously described in reference to the monotube) and thecompression damping rate correspondingly increases. In the embodiment ofFIGS. 14A-17E, the mechanism is somewhat different from the previouslydescribed monotube, as will be discussed below.

FIG. 14A depicts a perspective view of the shock absorber assembly, in acompressing state, in accordance with embodiments. FIG. 14B depicts across-sectional side elevation view of the shock absorber assembly ofFIG. 14A, in accordance with an embodiment, in which the damping unit1400 is shown proximate to the “bottom out” zone where needle 200 hasentered bore 235. Referring to FIGS. 14A and 14B, as well as FIGS.15A-17E, the shaft 205 has a piston assembly 1405, including a dampingpiston 310, mounted thereon. The piston assembly 1405 has a top 1410 anda bottom 1415 as indicated, each having a corresponding damping valve“shim” stack for compression and rebound (extension) damping resistance,respectively (the compression damping valve shim stack 1425 and therebound damping valve shim stack 1420). During a compression or reboundmovement occurring when the needle 200 is not within the bore 235,damping fluid flow resistance is achieved via the appropriate shims andfluid also flows between the top 1410 and the bottom 1415 of the pistonassembly 1405 through the bore 235 by way of shaft flow ports (includingthe compression port 145 and the rebound port 150 of FIG. 7) and pistonflow channels 305. When the needle 200 just enters (or just leaves) thebore 235 (e.g., during compression or rebound, respectively), it impedesfluid flow through bore 235 (hence increasing the damping rate fromfreeflow) by virtue of its “plugging” effect. Fluid flow however maycontinue with the needle 200 in that position. When the full diameter ofthe needle 200 is adjacent the shaft flow ports, as shown in FIG. 14B,the needle 200 substantially blocks the shaft flow ports and hencesubstantially blocks flow through the flow channels 305 and bore 235. Inone embodiment, such blockage effectively closes the bypass ports 320,thereby drastically reducing the available flow area through the dampingpiston 310.

FIG. 15A depicts a perspective view of aspects of embodiments, in anexpanding state, in accordance with embodiments. FIG. 15A shows thereservoir flow adjuster valve 1505 for adjusting the flow of fluid intothe reservoir 1510 of FIG. 15B. FIG. 15B depicts a cross-sectional viewof FIG. 15A, aspects of embodiments having a “piggy back” reservoir(versus a monotube), in an expanding state, in accordance withembodiments. FIG. 15B shows an adjustable spring keeper 1515, a woundhelical spring 1520, detail 1525 (an enlargement of detail 1525 is shownin FIG. 17D), detail 1530 (an enlargement of detail 1530 is shown inFIG. 17E), and bore 235.

As shown in FIG. 15B, damping unit 1400, shown fully extended, includesa cylinder 302 with a shaft 205 and a piston 310 fixed on one end of theshaft 205 and mounted telescopically within the cylinder 302. Dampingunit 1400 also includes a needle 200 configured to enter a bore 235 inshaft 205. However, damping unit 1400 does not include an annularfloating piston mounted substantially co-axially around the needle 200and axially movable relative thereto. Instead, the piggy back reservoir1510 includes a floating piston 1305 configured to perform the functiondescribed herein with regard to the internal floating piston. A volumeof gas is formed between the internal floating piston 1305 and one endof the piggy back reservoir 1510. The gas is compressed to compensatefor motion of shaft 205 into the cylinder 302. Excess damping liquid mayenter or exit cylinder 302 from the piggy back reservoir 1510 as thevolume of fluid changes due to ingress or egress of shaft 205 from thecylinder 302.

FIG. 16A depicts an enlarged cross-sectional top elevation view of thetop 1410 of the piston assembly depicted in FIG. 14B, in accordance withan embodiment. FIG. 16C shows bypass ports 320.

FIG. 16B depicts an enlarged cross-sectional top elevation view of thebottom 1415 of the piston assembly that is depicted in FIG. 14B, inaccordance with an embodiment. FIG. 16B shows the bypass ports 320 andthe flow channels 305. Section C-C is also marked on FIG. 16A and shownin a cross-sectional view of the piston assembly in FIG. 16D. FIG. 16Dshows the flow channels 305.

FIG. 16C depicts an enlarged cross-sectional side elevation view of thepiston assembly, in accordance with an embodiment. FIG. 16C shows thepiston 310 and detail 1605. FIG. 16F depicts an enlarged view of thedetail 1605, showing the piston 310, in accordance with an embodiment.

FIG. 16D depicts a cross-sectional side elevation view of FIG. 16A atthe Section B-B, in accordance with an embodiment. FIG. 16D shows thepiston 310.

FIG. 16E depicts a cross-sectional side elevation view of FIG. 16B atthe Section C-C, in accordance with an embodiment. FIG. 16E shows theflow channels 305 and the piston 310.

FIG. 17A depicts a perspective view of a shaft 205, in accordance withan embodiment. FIG. 17A also shows detail 1525 (of FIG. 15B) and detail1530 (of FIG. 15B).

FIG. 17B depicts a cross-sectional side elevation view of the shaft 205of FIG. 17A, in accordance with an embodiment. FIG. 17C depicts anenlarged view of the detail 1705 of FIG. 17B, in accordance with anembodiment. FIG. 17C also shows passageway 126 (shaft ports).

FIG. 17D depicts an enlarged view of the detail 1525 of FIG. 15B andFIG. 17A, in accordance with an embodiment. FIG. 17E depicts an enlargedview of the detail 1530 of FIG. 15B and FIG. 17A, in accordance with anembodiment. FIG. 17E shows passageway 126.

It should be noted that any of the features disclosed herein may beuseful alone or in any suitable combination. While the foregoing isdirected to embodiments of the present invention, other and furtherembodiments of the invention may be implemented without departing fromthe scope of the invention, and the scope thereof is determined by theclaims that follow.

1. A vehicle suspension damper comprising: a cylinder coupled to aneyelet assembly; a piston assembly disposed within said cylinder; anadjuster coupled with said piston assembly, wherein said piston assemblycompresses fluid as it moves within said cylinder and said adjusterobstructs a fluid flow from a first side of a piston of said pistonassembly to a second side of said piston, wherein said adjustercomprises: a shaft having an opening formed therethrough; a flowdistributor disposed within said piston; a rotatable valve disposedwithin said opening of said shaft, said rotatable valve comprising: asecond cylinder, said second cylinder having an aperture formed througha surface of said second cylinder, said second cylinder defining a pathfor flow of said fluid therethrough; a control rod having a first endand a second end, said second end of said control rod coupled to saidsecond cylinder; a motive source coupled with said rotatable valve, saidmotive source configured for providing input, wherein in response tosaid input, said rotatable valve rotates from said first position tosaid second position; and a damping adjustment lever coupled with saidfirst end of said control rod, said damping adjustment lever configuredto move said second cylinder from said first position to said secondposition, said first position orienting said aperture with said flowdistributor such that a fluid flow path is created, said second positionorienting said aperture with said flow distributor such that said fluidflow path is more restrictive when in said second position; a reboundport disposed within said piston assembly, said rebound port configuredto allow fluid to bypass said rotatable valve during a rebound stroke ofsaid piston assembly; a needle extending inwardly of said cylinder andhaving an end thereof positioned for receipt within a bore during atleast a portion of movement of said piston during said compressionstroke of said piston, said bore disposed within said shaft; and a valvedisposed at an opening of said bore, said valve comprising: a seat; aretainer clip; and a check valve disposed between said seat and saidretainer clip, said check valve having an inner diameter for receivingsaid needle therethrough, said inner diameter of said check valve havinga size such that an annular clearance exists between said inner diameterof said check valve and an outer diameter of said needle, an amount ofsaid annular clearance determining a damping rate of said valve; whereinthe retainer clip is located between the check valve and the shaft.